title: Immunohistochemical analysis of subcutaneous tissue reactions to methacrylate resin-based root canal sealers.
abstract: OBJECTIVE
  To investigate subcutaneous tissue reactions to methacrylate resin-based root canal sealers by immunohistochemical assessment of inflammatory/immunocompetent cell infiltration.
  
  
  METHODS
  Silicone tubes containing freshly mixed Epiphany SE sealer, MetaSEAL, Super-Bond RC sealer, or a zinc oxide-eugenol sealer (Canals) were subcutaneously implanted into the backs of Wistar rats. Solid silicone rods implanted in different animals served as controls. After 7, 14 and 28 days, connective tissue surrounding the implants (n = 8, each) was processed for immunoperoxidase staining using OX6 (reactive to major histocompatibility complex class II molecules), ED1 (reactive to macrophages), and W3/13 (reactive primarily to neutrophils), and the number of positively stained cells within each field (1.2 × 0.8 mm) was enumerated. Statistical differences were analysed with Friedman's test and Scheffe's test (comparisons between test materials) or Mann-Whitney's U-test (test-control comparisons).
  
  
  RESULTS
  Canals showed a significantly higher number of W3/13-positive cells (mostly neutrophils) than MetaSEAL at 28 days (P < 0.05). There were no significant differences in the numbers of OX6- or ED1-positive cells between each test material at any time point. Test-control comparisons revealed several significant differences for each antibody. This was most notable for ED1, where all the test materials at each time point, except for Epiphany SE at 28 days, showed significantly larger values than the corresponding controls.
  
  
  CONCLUSIONS
  All the methacrylate resin-based sealers tested showed a similar level of inflammatory/immunocompetent cell infiltration. MetaSEAL induced less-intense neutrophil infiltration than Canals. Controls exhibited milder infiltration of inflammatory/immunocompetent cells compared with all the test materials.
authors.affiliation: Division of Cariology, Operative Dentistry and Endodontics, Department of Oral Health Science, Niigata University Graduate School of Medical and Dental Sciences, Niigata, Japan. y-yamanaka@dent.niigata-u.ac.jp
authors.forename: Y
authors.initials: Y
authors.lastname: Yamanaka
authors.forename: Y
authors.initials: Y
authors.lastname: Shigetani
authors.forename: K
authors.initials: K
authors.lastname: Yoshiba
authors.forename: N
authors.initials: N
authors.lastname: Yoshiba
authors.forename: T
authors.initials: T
authors.lastname: Okiji
mesh_terms: D000818:Animals; D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D001896:Boron Compounds / Q000494:pharmacology; D002452:Cell Count; D003238:Connective Tissue / Q000187:drug effects / Q000473:pathology; D000949:Histocompatibility Antigens Class II / Q000032:analysis; D007124:Immunoenzyme Techniques; D007150:Immunohistochemistry; D007155:Immunologic Factors / Q000494:pharmacology; D018836:Inflammation Mediators / Q000494:pharmacology; D007958:Leukocyte Count; D051917:Leukosialin; D008214:Lymphocytes / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects; D008297:Male; D008689:Methacrylates / Q000494:pharmacology*; D008768:Methylmethacrylates / Q000494:pharmacology; D020556:Neutrophil Infiltration / Q000187:drug effects; D009504:Neutrophils / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D019279:Resin Cements / Q000494:pharmacology*; D012387:Root Canal Filling Materials / Q000494:pharmacology*; D040521:Subcutaneous Tissue / Q000187:drug effects* / Q000473:pathology; D013997:Time Factors; D015035:Zinc Oxide-Eugenol Cement / Q000494:pharmacology; D000097382:CD68 Molecule
chemical_list: D000911:Antibodies, Monoclonal; D015703:Antigens, CD; D015214:Antigens, Differentiation, Myelomonocytic; D001896:Boron Compounds; D000949:Histocompatibility Antigens Class II; D007155:Immunologic Factors; D018836:Inflammation Mediators; D051917:Leukosialin; D008689:Methacrylates; D008768:Methylmethacrylates; D019279:Resin Cements; D012387:Root Canal Filling Materials; D015035:Zinc Oxide-Eugenol Cement; C067980:CD68 antigen, human; D000097382:CD68 Molecule; C116337:OX-6 monoclonal antibody; C486893:epiphany sealer; C534239:metaseal; C049495:Super-bond